The 3B Divex 2020 sea mine clearing operation in Narva Bay of the northeast coast of Estonia continues this week, involving naval personnel from Latvia and Lithuania, as well as Estonia.
The project is in the process of removing submarine ordnance dating back to World War Two, with divers from all three countries undertaking the complicated task, ETV news show "Aktuaalne kaamera" reports.
As well as removing the sea mines, which will be safely disposed of elsewhere, the exercise brings benefits in terms of international cooperation and training.
Sea floor less than 50 meters deep in Narva Bay
Detritus on the sea bottom, less than 20 meters deep in places, and no more than around 50 meters in depth, in that part of the Baltic, includes the wreck of a fast-attack torpedo boat, as well as around 30 mines, 20 of which are likely to be removed during the current project.
Divers remove the mines after attaching a net to the device, which is then lifted to the surface via flotation bags before being taken to a safer, underwater location to be destroyed.
The mines' vintage and the windy conditions combine to make the job challenging, First lieutenant (Vanemleitnant) Priit Kaasikmäe of the Estonian Navy (Merevägi) told AK.
World War Two-era torpedo boat leaking fuel
The mines had to be removed because of the danger they presented to a pump being used to remove fuel from the wrecked torpedo boat, which has been leaking.
Alternative solutions will be found at a later date for removing any mines which are left over; the current operation lasts a week.
A total of around 25 naval divers from Estonia, Latvia and Lithuania are taking part in the 3B Divex exercise, using specialist, non-magnetic and low-acoustic equipment for safety.
Thousands of pieces of submarine ordnance removed from Baltic seabed since independence
The divers can descend to depths as much as 55 meters – on the brink of qualifying as a deep dive in the technical understanding, and 15 meters deeper than maximum depths encountered in recreational diving.
Over 1,400 explosive devices, mostly mines and other pieces of ammunition which have ended up on the sea bottom, have been discovered and rendered harmless in Estonian waters over the past 20 years.
President Kersti Kaljulaid recently witnessed at first hand the disposal of a sea mine in shallow water off Saaremaa.
The original AK report (in Estonian) is here.
Editor: Andrew Whyte